Theoretical Investigation of the Green-Synthesized Carbon-Based Nanomaterial Potential as Inhibitors of ACE2 for Blocking SARS-CoV-2 Binding.

Since the emergence of SARS-CoV-2 in 2020, the world has faced a global pandemic, emphasizing the urgent need for effective treatments to combat COVID-19. This study explores the use of green-synthesized carbon-based nanomaterials as potential inhibitors of ACE2, a critical receptor for SARS-CoV-2 entry into host cells. Specifically, the study examines four carbon-based nanomaterials, namely, CD1, CD2, CD3, and CD4 in amino, graphitic, pyridinic, and pyrrolic forms, respectively, synthesized from curcumin, to investigate their binding affinity with ACE2. Molecular docking studies revealed that CD3 (pyridinic form) exhibited the highest binding affinity with ACE2, surpassing that of the control compound, curcumin. Notably, CD3 formed hydrophobic interactions and hydrogen bonds with key ACE2 residues, suggesting its potential to block the binding of SARS-CoV-2 to human cells. Moreover, molecular dynamics simulations demonstrated the stability of these ligand-ACE2 complexes, further supporting the promise of CD3 as an inhibitor. Quantum chemical analyses, including frontier molecular orbitals, natural bond orbital analysis, and the quantum theory of atoms in molecules, unveiled valuable insights into the reactivity and interaction strengths of these ligands. CD3 exhibited desirable chemical properties, signifying its suitability for therapeutic development. The study's findings suggest that green-synthesized carbon-based nanomaterials, particularly CD3, have the potential to serve as effective inhibitors of ACE2, offering a promising avenue for the development of treatments against COVID-19. Further experimental validation is warranted to advance these findings and establish new therapies for the ongoing global pandemic.

Green synthesis of copper ions nanoparticles functionalized with rhamnolipid as potential antibacterial agent for pathogenic bacteria.

Copper-based nanoparticles possess broad-spectrum antibacterial activity against both gram-positive and gram-negative bacteria, making them a cost-effective alternative to other metal-based nanoparticles. The development of eco-friendly copper based nanopaticles using biodegradable and non-toxic biosurfactants, such as rhamnolipid is being explored in this study. In the present study, Cu(I)-rhamnolipid nanoparticles (Cu(I)-Rl Nps) was prepared by coprecipitation method. The structural analysis by using FTIR and XRD techniques revealed that Cu(I)-Rl Nps was successfully produced, as indicated by the detectable of ionic and covalent-coordinations bond between rhamnolipid and Cu(I) ions. Further analysis using TEM, PSA and ZPA suggest that the resulted Cu(I)-Rl Nps have spherical shape with the diameter range of 141.7-536.3 nm and the surface charge of -30 mV, respectively. The antibacterial activity of Cu(I)-Rl Nps surpassed that of the copper-based nanoparticles, free-state Cu(I) ions and rhamnolipid, which was determined by MIC/MBC methods. The Cu(I)-Rl Nps inhibition to the growth of Bacillus subtilis ATCC 6633 (Gram-positive) gave the MIC/MBC values of 19/19 µg/mL, while the copper-based nanoparticles, free-state Cu(I) ions and rhamnolipid gave the MIC/MBC value of 1250/2500, 1250/1250, 62/62 µg/mL, respectively. Further test on Escherichia coli ATCC 6538 (Gram-negative) showed that the Cu(I)-Rl Nps gave the MIC/MBC value of 78/78 µg/mL, while the copper-based nanoparticles, free-state Cu(I) ions and rhamnolipid gave the MIC/MBC value of 2500/2500, 2500/2500, 2000/2000 µg/mL, respectively. The increased antibacterial activity of Cu(I)-Rl Nps was due to the synergistic effects between Cu(I) and rhamnolipid.

Potential application of bisoprolol derivative compounds as antihypertensive drugs: synthesis and in silico study.

Two bisoprolol derivatives, N-acetyl bisoprolol and N-formyl bisoprolol, belonging to the beta-blocker class of antihypertensive drugs, were synthesized using acetylation and formylation reactions. The yields of the reactions were determined to be 32.40% for N-acetyl bisoprolol and 20.20% for N-formyl bisoprolol. In silico methods such as molecular docking, molecular dynamics simulation and SwissADME prediction were employed to evaluate the potential of these bisoprolol derivatives as antihypertensive drugs. These methods were used to assess the interaction between the bisoprolol derivatives and various receptors associated with hypertension, including human angiotensin I-converting enzyme (PDB ID: 1O8A), renin (PDB ID: 2V0Z), beta-1 adrenergic receptors (PDB ID: 4BVN, 7BVQ), voltage-dependent L-type calcium channel subunit alpha-1S (PDB ID: 6JP5) and mineralocorticoid receptor (PDB ID: 6L88). Our results demonstrated the highest binding energy when bisoprolol and its derivatives bound to 4BVN, with binding energy values of 6.74 kcal mol-1, 7.03 kcal mol-1 and 7.63 kcal mol-1 for bisoprolol, N-acetyl bisoprolol and N-formyl bisoprolol, respectively. The stability of these complexes was confirmed by molecular dynamics simulations, with a root-mean-square deviation value of approximately 2. Furthermore, the SwissADME results indicated that both derivatives exhibited similar properties to the reference drug bisoprolol.

In Vitro and Silico Studies on the N-Doped Carbon Dots Potential in ACE2 Expression Modulation.

The alteration of ACE2 expression level, which has been studied in many diseases, makes the topic of ACE2 inducer potential crucial to be explored. The ACE2 inducer could further be designed to control the ACE2 expression level, which is appropriate to a specific case. An in vitro study of well-characterized carbon dots (CDs), made from citric acid and urea, was performed to determine their ability to modulate the ACE2 receptor. Gene expression of ACE2 was quantified using concentrations adjusted for IC50 results from CDs viability assays in HEK 293 and A549 cell lines. RT-qPCR was used to assess the expression of the ACE2 gene and its induction effect in normal cell lines (HEK-293A). According to the results of the tests, ACE2 is expressed in HEK-293A cell lines, and diminazene aceturate can increase ACE2 expression. The effect of CDs on ACE2 gene expression was further examined on the cell lines that had previously been induced with diminazene aceturate, which resulted in upregulation of the ACE2 expression level. An in silico study has been done by using a molecular docking approach. The molecular docking results show that CDs can make strong interactions with ACE2 amino acid residues through hydrophobic interaction, π-π interaction, π-cation interaction, and ionic interaction.

Graphene quantum dots functionalised with rhamnolipid produced from bioconversion of palm kernel oil by Pseudomonas stutzeri BK-AB12MT as a photocatalyst.

Methylene blue (MB) is a common organic dye found in textile wastewater and can harm the environment. Rhamnolipid-functionalized graphene quantum dots (RL-GQDs) are a newly developed eco-friendly photocatalyst to degrade MB. This photocatalyst is synthesized from graphene quantum dots (GQDs) and rhamnolipid. GQDs are already promising visible-light photocatalysts to degrade organic dyes. However, GQDs are not promising photocatalysts due to their reusability and photocatalytic performance. In this work, we used rhamnolipid to modify GQDs' structure and enhance their photocatalytic performance. The rhamnolipid used in this work was produced from bioconversion of palm kernel oil by mutated bacterial cells of Pseudomonas stutzeri BK-AB12MT. Meanwhile, GQDs were synthesized using the bottom-up method by pyrolysing citric acid. Transmission electron microscopy and Fourier-Transform Infrared spectroscopy were used to characterize these hybrid materials. These characterization techniques verified the formation of RL-GQDs. To prove the photocatalytic performance of RL-GQDs, we investigated the photocatalytic activity under visible light compared to some common photocatalysts, such as zinc oxide and titanium dioxide. Our findings showed that RL-GQDs could be applied as an eco-friendly photocatalyst to replace TiO2 with a degradation efficiency of 59% ± 3% under visible light irradiation, higher than TiO2.